FROGLOGGER PROTOCOL

Protocol for Big Bend National Park Monitoring Field Crews

We use frogloggers to automatically record chorusing amphibians in the field.  The automated recording system was designed by Michael Dorcas (Peterson and Dorcas 1994).   Details on froglogger construction are available from Robin Jung.  We use the frogloggers to record amphibian chorusing over the course of 4 days.

SETTING UP THE FROGLOGGER

· Use a 12 volt battery that is fully charged.  The recharger should blink the red light 5 times and then read "full" when it is first hooked up.  It may take the recharger 15 minutes before it is finished reading the battery.  Be careful not to short out the recharger by touching leads to each other.

· Hook the red and blue wires in the froglogger up to the battery.

· Wind the cassette tape forward by hand so that the clear (unrecordable) tape is gone. Only one side of the tape can be used at a time. Tapes must be flipped over by hand.

· Check that the cassette recorder is on "headphone" to record.

· Check that the time is correct on the voice clock.

· Place the small microphone inside near the voice clock.

· Set the relay settings on the timer to record for 16 seconds every 30 minutes.

ON (seconds) OFF (minutes) Left (L) means it is "on", right (R) means it is "off".

0.1 R 0.1 R
0.2 R 0.2 R
0.4 R 0.4 L
0.8 R 0.8 L
1.6 R 1.6 R
3.2 L 3.2 L
6.4 R 6.4 R
12.8 L 12.8 R
25.6 R 25.6 L
51.2 R 51.2 R

· Press down the record button together with the play button on the cassette recorder.

· Turn toggle switch to ON.

· Voice clock should announce the time.

· The cassette should record for 16 seconds and then stop.

SETTING UP THE FROGLOGGER IN THE FIELD

Find a concealed place near water to hide the froglogger.  Try to avoid placing the froglogger in a drainage where it may be disturbed by flooding.  Make sure the microphone is surrounded by foam and secure inside the plastic soda bottle cover.   The microphone is attached to a dowel rod, which should be secured to vegetation or placed into the ground.  Label the tape and case with location, date, recording time interval, and froglogger ID number.  Check to make sure the froglogger records properly and stops after 16 seconds.  At the start of  recording, announce the location, date, and time.  Cover the froglogger box with a reflective sun-barrier and secure the sun-barrier to vegetation or tuck underneath the box.  Make sure there is a sign reading "Big Bend National Park, Frog study" attached to the sun-barrier. Take a GPS reading for UTM cordinates.

Retrieve the froglogger 4 days later (for a 120 min tape).  If there is still tape left, record the date and time of removal.  Make sure the tape is labeled and write the date out (e.g., 4 July 1998) on it. Either flip tape over for another 4 days of recording (need to switch batteries also) or remove entire froglogger.

IN THE FROGLOGGER FOLDER

Record the location and date in (date started recording). When the froglogger is removed, record the date out (date ending recording).  Any notes on weather or amphibians seen at the location can be recorded here.

RECORDING DATA FROM THE TAPES

On the Froglogger Data Sheet, write down the begin date and time of recording, end date and time, location, UTM coordinates (if known), name of person recording data off of the tape, date listened to, recording time interval (should be 16 sec/30 min.), and tape side A or B.

To listen to recording, switch cassette recorder to "speaker."  Listen to the tape (headphones work best).  Record the start time announced on the tape.   Any time an amphibian chorus is heard, record the time, species, and chorus code (CC).  Chorus code: 0 = none heard, 1 = no overlapping calls, 2 = some overlapping calls, 3 = full chorus.  For chorus codes 1 and 2, estimate the number of individuals heard and place in parentheses after the chorus code.  Example: 21:50 Goli 2(4).

Record anything else heard on the tape (e.g. insects, owls, people, fighter jets).

If the froglogger does not work properly, record the time when it malfunctions (e.g., 14:30 Tape kept recording, timer not working).  If this happens, continue recording data off the tape and estimate time of frogs calling from real time based on when the timer stopped functioning.

RECOMMENDATIONS

Find water areas in the Park where frogloggers can be placed permanently to record calls all summer long.  Possibilities include Glenn Springs, Beaver pond, Daniel's Ranch, and Boot Spring.

Place rain gauges at the froglogger sites in the open such that no vegetation intercepts the rainfall.

Watch for pools of water formed after rains in culverts alongside paved roads.   These are often used for short-term intense breeding by Scou, Goli, and Bdeb.   Two good culvert pools are along Route #11 (Persimmon Gap road) at mile 8.8 from Panther Junction on the east side of the culvert and mile 9.2 at Star Creek also on the east side.

These two figures show the chorus codes summing over a 4-day period of amphibians following a rain event at one site in the Park.  The frogloggers were set up facing east and west of the culvert.  It is interesting to note that even though the frogloggers were recording at the same site, at the same time, the direction which the frogloggers faced revealed differences in the number of species recorded, phenology, and chorus code assignments.

Reference  

PRIMENet Amphibian Monitoring Program Homepage

Patuxent Homepage